Odor Memories

by Srishti Batra – Do you ever wonder how a smell can take you back in time? The sense of smell is closely associated with memory. At a certain point, all of us have experienced smells that evoke memories. For example, the aroma of freshly brewed coffee takes me back on my first date where I enjoyed a beautiful conversation over coffee.

At some point in life, all of us have experienced olfactory memory. There has been a lot of research to understand how odor gets associated memories, and one crucial thing needed to understand that is achieved by studying the processing of odor in the brain. If we understand how brains perceive and process smell, we can understand olfactory memories better.

During my doctoral research, I am trying to understand how brains perceive smells. I work on Drosophila, a tiny fruit fly of about 1-5 mm in size and with a tiny brain. Whenever I try to explain my doctoral work to a non-scientific audience like my parents, friends etc.; the most common question I face is why should we study fruit flies and do they have brains?

My answer to all people having similar doubts: Fruit flies share about 60% of human genes and all the basic cellular and molecular process are the same in flies and humans. This makes the fly a very useful tool to study some basic problems in science. And “YES”, fruit flies have brains. However, their brain is much tinnier at less than 1mm in size and it is made up of around 200000 neurons. Studying brains with many neuronal connections is not an easy task, but we have amazing tools and techniques where we can mark a single neuron or set of neurons and study them. See this beautiful picture of a fly brain where specific neurons are marked in green color. This fly brain was dissected by Gauri in our lab and is imaged using confocal microscopy.